Clive's 400 BHP Super GT RX-8 Race Car

[clive]

Thank you, but the alternator does not run through the the ECU nor does the ignition as this has an independent circuit and feed directly from the cut out switch.

Going to try and find the time later to change the ECU back to the original unit that came with the car.

I had another ECU integrated into the car when I was trying to solve the way back electric issues, hopefully the car still recognises the original.     

[boosted]

What i mean is if the regulator Rectifier is playing up you may have greater voltage than 12v on all your subsystems...alternator rectifier should not put out more than 14.4 v...so if say spiked 16v then the stepdown transformer circuit in the pcm would be higher than 5v..so all return signals etc would re input higher than normal voltages..and thats what some of the codes are showing. Circuit higher than referenced values.
Just an easy test across the battery with the car running and few revs to make sure stable 14.4v.

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[boosted]

To put it another way....where does the volts running the ecu come from...the battery and alternator and will run on the highest voltage it sees...may not be the issue but easy check to rule out....difficult to explain what i mean...

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[clive]

No feeds are being used from the alternator feeds, no idea without checking to know what actually powers up the ECU but I suspect that this is still from the ignition feed that's no longer powering the coils.

LCLewis called and he is convinced that the only thing that will keep the car in limp mode is the OMP, got one some where so I will have a try at this first. 

[Casey]

The volts have to come from the battery, which is being charged by the alternator, so the ECU will see the alternator voltage when the engine is running as they are all connected when ignition is on. I'm not aware you have any other power source other than the alt or battery?? So Jon's point is still valid, as is the OMP theory.

[boosted]

P0108 is barometric sensor i know without 1 fitted car will not run...this again is circuit high which suggest a very high input back into pcm...
What happens when you clear codes...do these come straight back...

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[Casey]

Yes, they came straight back when Clive cleared them at the circuit, did a ECU reset and ran the engine again. Limp mode straight away and codes back as before.

[Casey]

Just been thinking. Was it right to do an ECU reset? This will clear all the eccentric shaft plate data which then takes the car a while to relearn? If I recall correctly, the car then has to go through a "drive cycle" (including leaving the car to idle for 10mins or so) before the engine relearns all the settings/trims.

Maybe off beam, but thought worth adding, in case relevant.

Also found this on RX8club.com

"Typical limp mode is a 4k rev limit but should act somewhat normally below that, though pretty down on power. I say "typical", because there are a few different limp modes, for example there is a "limp mode" for an accelerator pedal position sensor failure that pegs the RPM at 3,000rpm regardless of the temp of the car and what you are doing with the pedal."

However, wouldn't that failure have thrown up a code?

[boosted]

Hang on....ecu reset ecu learn 2 different things...dont think the 20 brake stomp actually clears codes never actually tried to clear codes that way...its for relearning e shaft profile and resetting fuel trims.
Ecu reset should be done with a scan tool..clear codes and rescan data.
Doing a 20 brake stomp shouldnt cause any issues.

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[re japi]

I was listening 2nd race live commentary  from link that Lisa shared... And I was really sorry for Clives bad luck. But good thing is that you were more than second faster than your previous outing. It shows good progres

Lähetetty minun E2303 laitteesta Tapatalkilla

[Casey]

Short drive-by video of Clive's car in 1st race:

[boosted]

Defo looks like got some speed !

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[Casey]

A few pics too.....

Clive in the 1st race, and his retirement about 1 lap from the end.

..................and some of the competition in the same race 

[rote8]

I think I am going to refrain from wishing you good luck Clive, it seems more like the kiss of death.  Sorry to hear of the latest woes, especially as it is another 'odd one', you don't seem to do simple.

[clive]

OK, Here go------------Christine strikes again   

Changed OBD, no reboot, no good 

Changed Mazda ECU for the origonal, no reboot, and it's a revving  SUCCESS